Portable grinder



July 18, 1939. w. c. DRAHEIM PORTABLE GRINDER Filed Oct. 17, 1938 2 sheets Sheet 2 Inventor Patented July 18, 1939 UNiTED STATES PATENT OFFICE 1 Claim.

This invention relates to portable, hand grinders, and an object of the invention is to, generally, improve upon such types of grinders as are now known and used.

The invention together with its objects and advantages will be best understood from a study of the following description taken in connection with the accompanying drawings wherein:

Figure l is an elevational view of a grinder showing the same from one side thereof.

Figure 2 is a top plan view of a grinder embodying the features of the present invention.

Figure 3 is an elevational view of the grinder, viewing the same from the side thereof opposite to that shown in Figure 1.

Figure 4 is a sectional view through the grinder showing certain details hereinafter more fully referred to. l

Figure 5 is a detail sectional view also illustrating certain details hereinafter more fully referred to, and

Figure 6 is a plan view of a gauge bar forming part of the invention.

Referring more in detail to the drawings it will be seen that in the preferred embodiment thereof the grinder comprises a frame 5 provided at the forward end thereof with a suitable handle knob 6 and at the rear end thereof with a suitable integral handle 1.

The frame 5 is substantially completely closed on one side thereof and open on the opposite side as shown.

Accommodated Within the frame 5 is a rotary tool 8 which, in the present instance is in the form of an emery wheel. The wheel 8 is suitably mounted on a shaft 9 which has an end extending into a bearing housing Hi that projects from the closed side of the frame 5. The bearing housing H3 at one end thereof is provided with a flange ll through the medium of which and screws or other fastening elements l2 said bearing housing is secured to one side of the frame 5.

Arranged within the bearing housing H! for accommodating the shaft 9 are suitable anti-friction devices or bearings 3 as shown in Figure 4.

If desired, an electric motor may be directly connected with the shaft 9 for driving the tool 8, or, and as shown in Figure 4, there may be suitably coupled to the shaft 9 as at M one end of a flexible driving shaft 15 feeding from any suitable source of power.

Further in accordance with the present invention there is provided a substantially rectangular frame-like gauge bar 16 which at one end thereof is pivoted to the handle-equipped end 1 of the frame 5 adjacent the bottom of the frame as at IT.

Pivoted between the sides of the frame IE5 at the opposite end thereof is the crosshead of a T-shaped screw I8 that is accommodated by an 5 apertured lug l9 provided on the forward end of the frame 5 as shown.

Engaged with the screw i 8 above and below the lugs l9 are adjusting screws 20.

Manifestly with the nuts 29 loose on the bolt iii the gauge bar l5 may be swung on its pivot [1 to the desired position of adjustment and held in said position of adjustment by threading the nuts home on the bolt l8. To accommodate the nuts 20 the frame 5 at the forward end thereof is provided with a vertical groove 2| as best shown in Figure 5.

To accommodate the flange ll of the housing It] the gauge bar H5 at one side thereof is provided with an arcuate notch 22 in the upper edge of said one side.

At the opposite side thereof the gauge bar It has a portion thereof removed to provide for the accommodation of the periphery of the tool or grinding wheel 8, and the terminals of the bar 25 resulting from the formation of this space have arcuate edges 23 to conform to the periphery of the wheel 8, the arcuate edges 23 thus providing therebetween a slot in said side; of the gauge bar l6 for the grinding tool or wheel 8.

Obviously, in operation the wheel or tool 8 will be driven from a motor mounted on the tool if desired, or from a source of power remote from the tool and through the medium of the flexible driving shaft [5, at a suitable speed. The operator places one hand on the handle knob 6 and with the other hand grips the handle I for moving the tool across the surface to be operated upon, the operating tool quickly removing the material of such surface to the desired extent and as the cutting depth of the tool is controlled by the adjustment of the gauge I6.

It is thought that a clear understanding of the construction, operation and utility of a machine of this character will be had without a more detailed description thereof.

Having thus described the invention what is claimed as new is:

A grinding machine of the class described comprising a vertically arranged and longitudinally elongated narrow body having a circular opening in one side thereof, the lower edge of the body being substantially flat with the opening extending through an intermediate part of said edge,

a circular tool located in the opening, a horizonthe other end portion of the bar, a perforated projection at the front end of the body through which the screw passes, upper and lower nuts on the screw between which the projection is located, said bar having its side portions located adjacent the side faces of the body, with the free limbs of the U-shaped portions having their inner ends curving downwardly and inwardly to form a space between them for receiving a portion of the tool.

WILLIAM C. DRAI-IEIM. 

